Safety device for use with automatic automobile window regulator

ABSTRACT

A safe automatic window regulator so designed that if the human body and the like touches the upper end of the window glass, it is sensed so that even if the switch has been closed in the direction to close the window, the electric circuit is automatically changed over so as to reopen the window thereby preventing harm to the human body and the like due to any inadvertency.

United States Patent Ito et al. 1 Mar. 21, 1972 54] SAFETY DEVICE FORUSE WITH [56] References Cited AUTOMATIC AUTOMOBILE WINDOW UNITED STATESPATENTS REGULATOR 3,409,842 11/1968 Emblins et al. ..331/65 1 lnvemors=shlsehiko Karlya-shi; l'llmshi Ami, 3,513,374 5/1970 Koment ..3l8/266Toyota-SM, both of Japan v 3,525,028 8/1970 Ruoss et al ..3l8/478 [73]Assigneez Nippon Denso Kabushiki Kaisha, Showa 3,200,304 8/1965 Atkms etal ..200/DIG. 1

Kanya'shl Alchl'ken Japan Primary Examiner-Gene Z. Rubinson [22] Filed:Nov. 3, 1969 Assistant Examiner-W. E. Duncanson, Jr.

Attorney-Cushman, Darby & Cushman [21] App1.No.: 873,320

[57] ABSTRACT Ffil'eign pp fi P F113! 1 A safe automatic windowregulator so designed that if the human body and the like touches theupper end of the window Nov. 9, 1968 Japan ..43/97823 g it is sensed sothat ave" if the Switch has been closed in the direction to close thewindow, the electric circuit is auto- [31 US. Cl ..3l8/266, 318/2820?8/42; maticauy changed over so as to reopen the window thereby 1 pl/preventing harm to the human body and the like due to any in- [58] Fleldof Search ..3 18/266, 286, 466, 478; 1

317/123 P; 340/258; ZOO/DIG. 1

advertency.

5 Claims, 1 Drawing Figure SAFETY DEVICE FOR USE WITH AUTOMATICAUTOMOBILE WINDOW REGULATOR BACKGROUND OF THE INVENTION 1. FIELD OF THEINVENTION The present invention relates to a safety device for use withautomatic automobile window regulators, which automatically stops therising movement of the window glass to prevent any harm to the humanbody, shuld a hand or the like be caught between the window glass andthe window frame.

2. DESCRIPTION OF THE PRIOR ART Conventionally, the vertical movement ofan automobile ;.'window glass was effected by manually turning thehandle to an electric motor. However, such powered windows are verydangerous in a sense, because, if its switch is operated by mistake by achild and the like and a hand or the like is caught .between the windowglass and the window frame, the window glass will nevertheless continueits upward movement with the hand or the like being caught therebetween.

SUMMARY OF THE INVENTION The general object of the present invention isto provide a highly safe automatic window regulator wherein, if a partof the human body and the like touches the upper end of the windowglass, it is sensed so that, even if the switch has been closed in thedirection to close the window, the electric circuit is automaticallychanged over so as to reopen the window to thereby prevent hurt to thehuman body and the like due to an inadvertency.

More specifically, the object of the present invention is to providewhat is stated in the claim.

According to the present invention, a relay circuit for deoscillatingtransistor is connected to an electrode mounted on the upper end of thewindow glass, and a high-frequency oscillation circuit is employed asthe said oscillation circuit whose oscillation frequency is determinedby the inductance and stray capacitance of the oscillating coil and bythe stray inductance and stray capacitance of the base circuit of theoscillatin g transistor, whereby the oscillating condition of theoscillation circuit in the device of the present invention is made verycritical so that a very slight electrical change in the base circuit ofthe oscillating transistor caused by a hand or the like touching theelectrode may readily cause the oscillation circuit to start or stop itsoscillation, hence not only the detection sensitivity is excellent butalso the external appearance of the window is not spoiled since thesensing means comprises merely an electrode of a very simpleconstruction such as a conductor foil. These are the remarkable effectsattributable to the present invention.

Moreover, because the oscillating transistor is provided with an emitterbias resistor and a portion of this bias resistor is composed of avariable resistor to accomplish a negative feedback from this variableresistor to the oscillating transistor, there is a further advantagethat the magnitude of the negative feedback to the oscillatingtransistor is changed according to the resistance value of the variableresistor to adjust the stability of the oscillation circuit therebyachieving the adjustment of the sensitivity of the oscillation circuitvery easily. Furthermore, there is anotheradvantage that there is noneed to especially provide a transformer and the like in the outputcircuit of the oscillation circuit, since the oscillation output istaken out from the said emitter bias resistor.

BRIEF DESCRIPTION OF THE DRAWING The accompanying drawing is anelectrical wiring diagram showing an embodiment of the presentinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention will beexplained hereinafter in conjunction with the illustrated embodiment. Inthe accompanying drawing, numeral 1 designates a power source such as astorage battery, and 2 a switch in which a movable contact 2c ismanually operated to contact with either one of fixed contacts 2a and2b. Numeral 3 designates an electric motor for operating the windowregulator which is so constructed that it makes a forward rotation whenthe motor is energized through a field coil 3a, and that the directionof rotation of the motor is reversed when it is energized through theother field coil 3b. Numeral 4 designates a relay circuit according tothe present invention, and 401 an antenna connected to an electrode suchas a conductor foil mounted on the upper end of the window glass.Numeral 402 designates a capacitor to block the relay circuit 4 from theantenna 401 with respect to the DC component. Numeral 403 designates aresistor, and 404 a capacitor to block the DC component. Numeral 405designates an oscillating coil, and 406 also designates an oscillatingcoil, both 'coils being wound so that they have their polarities set asshown by the mark in the drawing. Numeral 407 designates an oscillatingtransistor, and the oscillation circuit composed of the transistor 407and the coils 405 and 406 forms a high-frequency oscillation circuitwhose oscillation frequency is of the order of several MHz. Here, theoscillation frequency of the oscillation circuit is determined by theinductance and stray capacitance of the oscillating coil 405 on the sideof the base of the oscillating transistor 407 and by the strayinductance and stray capacitance of the base circuit of the oscillatingtransistor 407. Numeral 408 designates a variable resistor constitutinga portion of the emitter bias resistor for the oscillating transistor407, and 409 a resistor constituting also a portion of the emitter biasresistor for the transistor 407, a bypass capacitor 410 being connectedin parallel with the resistor 409. Numeral 411 designates a biasresistor for a transistor 412; 413 and 414 capacitors to ensure theconduction of the transistor 412 upon applying the source voltage to thecircuit so that a relay coil 418 will not be operated by mistake due tothe conduction of a transistor 416. Numeral 415 designates a loadresistor of the transistor 412. The transistor 416 forms a Schmittcircuit with the transistor 412. Numeral 417 designates a common emitterresistor of both transistors 412 and 416, which provides a hysteresiseffect for the on-off operations. Numeral 419 designates a movablecontact actuated by the relay coil 418 and 420 and 421 a normally closedfixed contact and a normally open fixed contact associated with themovable contact, respectively. I

With the construction described above, the operation of the deviceaccording to the present invention will be explained hereinafter. Now,assuming that the movable contact 20 of the switch 2 is caused tocontact with the fixed contact 20 to close the window, current issupplied to the electric motor 3 through the field coil 3a, and themotor 3 makes a forward running, whereupon the window glass is movedupward. At this instance, the relay circuit 4 is supplied with thesource voltage through the contacts 2c and 2a, so that the oscillationoperation of the oscillating transistor 407 is caused by the feedbackaction between the oscillating coils 405 and 406, and the oscillationoutput voltage of the transistor appears across the resistors 408 and409. This causes the potential raise at the junction point Aof theresistors 408 and 409, and the transistor 412 in the succeeding stageconducts, so that the transistor 416 is brought into a nonconductingstate, and the relay coil 418 remains deenergized, thereby leaving themovable contact 419 to be in contact with the normally closed fixedcontact 420. On the other hand, since the antenna 401 of the relaycircuit 4 is connected with the electrode mounted on the upper end ofthe window glass or in the vicinity thereof, if a portion of the humanbody such as a hand and the like touches the said electrode, it isequivalent to that the base of the oscillating transistor 407 isgrounded by means of a certain capacitance of the human body, and theoscillating condition of the oscillation circuit including thetransistor 407 collapses thereby stopping the oscillation.

Here, as the oscillation circuit comprising the oscillating transistor407 and the oscillating coils 405 and 406 are formed as a high-frequencyoscillation circuit whose frequency of oscillation is determined by theinductance and stray capacitance of the oscillating coil 405 and by thestray inductance and stray capacitance of the base circuit of theoscillating transistor 407, the waveform of the generated output is veryunstable and the condition for oscillation of this oscillation circuitis made extremely critical. It is thus possible to readily stop theoscillation of the transistor 407 by simply causing a small portion ofthe electric signal feedback to the oscillating transistor 407 to leakto the ground through the human body and the like. It is to be recalledhere that the emitter bias resistors 408 and 409 is inserted into theemitter circuit of the oscillating transistor 407, and the variableresistor 408 is employed as a portion of this bias resistor toaccomplish a negative feedback from the variable resistor 408 to theoscillating transistor 407, and the sensitivity of the oscillationcircuit may be thereby readily adjusted, because any adjustment of themagnitude of the variable resistor 408 to change the amount of thenegative feedback will change the oscillating condition of theoscillation circuit and subsequently the stability of the oscillation.Then, since the succeeding stage transistor 412 is driven into cut offand the transistor 416 conducts when the oscillating transistor 407stops its oscillation as previously described, a current is sup plied tothe relay coil 418, and the movable contact 419 comes into contact withthe normally open fixedcontact 421. This causes a current to flow intothe electric motor 3 through the reversing field coil 3b, hence thewindow glass in the upward movement is reversed. The instant anobstacle, such as the hand or the like, is removed, the oscillatingtransistor 407 starts its oscillation again, and the transistor 412conducts thereby cutting off the transistor 416, whereby the movablecontact 419 comes into contact with the normally closed fixed contact420 thus causing the window glass to move upward again. In this case, alimit switch and the like may be employed to detect the position of thewindow glass when it has moved up to the position where the upper end ofthe window glass contacts with the window frame to thereby prevent therelay coil 418 from being actuated again. By this means, such anundesired operation may be avoided that, although no hand or the like iscaught between the electrode and the window frame, the relay coil 418should be energized by the capacitance between the electrode and thewindow frame, and that the direction of the rotation of the electricmotor 3 should be thereby reversed to cause the window glass to godownwards even under such a normal operation condition. Instead ofemploying a limit switch, the window frame may be formed so that onlythe electrode section of the antenna 401 may be free from the contactwith the window frame when the upper end of the window glass reaches theposition where it contacts with the window frame. The present inventionwill not be limited to those in which the window regulation is effectedby means of an electric motor, but is equally applicable to a pneumaticor a hydraulic window regulator if a relay is utilized to control theopening and closing of the pneumatic or the hydraulic circuit.

Now, referring to the experiments conducted with the following componentparts: the oscillating coil 405-diameter of winding 15 4), number ofturns 25; oscillating coil 406- diameter of winding 10 (1;, number ofturns IS; the capacitor 4020.00l to 0.01 f; the resistor 403-1MQ; thecapacitor 402-500 pf. to 0.l 11; the electrode of the antenna 401-aconductor foil; and the oscillation frequency of the oscillation circuit4 to 5 MHz, the results obtained from the experiments have shown thatthe upward movement of the window glass was exactly prevented when thesaid electrode was touched with a hand.

We claim: 1. A safety device for use with automatic automobile windowregulators wherein a reversible window regulating motor is provided forraising and lowering at least one window glass, said safety devicecomprising:

an oscillation circuit comprising an oscillating transistor, seriesconnected emitter bias resistors connected to the emitter of saidtransistor, oscillation coil means connected between the collector andthe base of said transistor, and an electrode for mounting on the upperend of said window glass and connected to the base of said transistor,said oscillation circuit being oscillatable with a high frequency whichis determined by the inductance of said oscillation coils and by thestray capacitance and the stray inductance of said electrode, one ofsaid emitter bias resistors being a variable resistor for adjusting theamount of negative feedback from the emitter to the base of saidoscillating transistor by varying the resistance thereof, the other ofsaid resistors being bypassed by a capacitor and oscillation output ofsaid oscillation circuit being taken from the junction of said emitterbias resistors;

a relay and a relay control circuit, said relay control circuit beingresponsive to said oscillation output for controlling the energizationof said relay; and

means in said control circuit for automatically reversing said windowregulating motor to lower said glass in response to operation of saidrelay.

2. A safety device as in claim 1, wherein said emitter bias resistorsare connected between the emitter of said transistor and ground, saidoscillation coil means comprising a first oscillation coil connected tothe collector of said transistor and a second oscillation coil connectedto the base of said transistor, and wherein a coupling capacitor isconnected between said electrode and the base of said oscillatingtransistor.

3. A safety device as in claim 2, wherein said oscillation circuitfurther comprises a DC blocking capacitor connected in series withsecond oscillation coil, and a resistor connected between the base ofsaid transistor and said power source.

4. A safety device for use with an automatic automobile window regulatorhaving a power source, a window regulator motor, and a manual switch forchanging the direction of said motor to open or close a window glass,comprising:

electrode detecting means adapted to be mounted on said window glass forsignalling the presence of an adjacent human object by changing itsstray impedance,

a transistorized oscillator circuit electrically connected to saidelectrode and coil structured to change its normal operation into anabnormal operating condition when and only while the stray impedance ofsaid electrode means changes as aforesaid, and

means connected'to said oscillator circuit and responsive only to saidabnormal condition for automatically reversing said motor to cause saidglass to move in an opening direction while said manual switch is in aposition normally to cause closing of the glass so as to prevent saidhuman object from being caught by closing glass,

said reversing means being also responsive immediately upon cessation ofsaid abnormal condition and return of said oscillator circuit to itssaid normal operation due to sufiicient removal of said human objectfrom said electrode detecting means to effect automatic re-reversing ofsaid motor so that said window glass resumes its movement in the closingdirection while the said manual switch remains in its said normalclosing position.

5. A safety device as in claim 4 wherein said oscillator abnormaloperating condition is a non-oscillating condition and said electrodedetecting means is a conductor foil adapted to mount on the closing edgeof said window glass.

2. A safety device as in claim 1, wherein said emitter bias resistorsare connected between the emitter of said transistor and ground, saidoscillation coil means comprising a first oscillation coil connected tothe collector of said transistor and a second oscillation coil connectedto the base of said transistor, and wherein a coupling capacitor isconnected between said electrode and the base of said oscillatingtransistor.
 3. A safety device as in claim 2, wherein said oscillationcircuit further comprises a DC blocking capacitor connected in serieswith second oscillation coil, and a resistor connected between the baseof said transistor and said power source.
 4. A safety device for usewith an automatic automobile window regulator having a power source, awindow regulator motor, and a manual switch for changing the directionof said motor to open or close a window glass, comprising: eleCtrodedetecting means adapted to be mounted on said window glass forsignalling the presence of an adjacent human object by changing itsstray impedance, a transistorized oscillator circuit electricallyconnected to said electrode and coil structured to change its normaloperation into an abnormal operating condition when and only while thestray impedance of said electrode means changes as aforesaid, and meansconnected to said oscillator circuit and responsive only to saidabnormal condition for automatically reversing said motor to cause saidglass to move in an opening direction while said manual switch is in aposition normally to cause closing of the glass so as to prevent saidhuman object from being caught by closing glass, said reversing meansbeing also responsive immediately upon cessation of said abnormalcondition and return of said oscillator circuit to its said normaloperation due to sufficient removal of said human object from saidelectrode detecting means to effect automatic re-reversing of said motorso that said window glass resumes its movement in the closing directionwhile the said manual switch remains in its said normal closingposition.
 5. A safety device as in claim 4 wherein said oscillatorabnormal operating condition is a non-oscillating condition and saidelectrode detecting means is a conductor foil adapted to mount on theclosing edge of said window glass.